Gaskets are well-known devices for creating a seal between two parts. In some instances, one kind of gasket material is preferable over another material for certain applications. The preference for one material over another might be because of the performance characteristics of the gasket material. In some cases, the higher performing gasket material is more expensive. The resulting gasket is often entirely constructed of the more expensive, higher performing material.
This is disadvantageous because the expensive material might be used in certain locations or applications that does not call for higher performing gasket material. It would be preferable to only selectively use the higher performing, more expensive gasket material only where it is needed in an application and then use a less expensive material where the higher performing material is not needed.
It would also be advantageous to selectively use two different gasket materials for a sealing application and join those materials to one another without having to make accommodations in the mating parts for the joint.